Dominant Factors Governing the Rate Capability of a TiO₂ Nanotube Anode for High Power Lithium Ion Batteries

Abstract

Titanium dioxide (TiO(2)) is one of the most promising anode materials for lithium ion batteries due to low cost and structural stability during Li insertion/extraction. However, its poor rate capability limits its practical use. Although various approaches have been explored to overcome this problem, previous reports have mainly focused on the enhancement of both the electronic conductivity and the kinetic associated with lithium in the composite film of active material/conducting agent/binder. Here, we systematically explore the effect of the contact resistance between a current collector and a composite film of active material/conducting agent/binder on the rate capability of a TiO(2)-based electrode. The vertically aligned TiO(2) nanotubes arrays, directly grown on the current collector, with sealed cap and unsealed cap, and conventional randomly oriented TiO(2) nanotubes electrodes were prepared for this study. The vertically aligned TiO(2) nanotubes array electrode with unsealed cap showed superior performance with six times higher capacity at 10 C rate compared to conventional randomly oriented TiO(2) nanotubes electrode with 10 wt % conducting agent. On the basis of the detailed experimental results and associated theoretical analysis, we demonstrate that the reduction of the contact resistance between electrode and current collector plays an important role in improving the electronic conductivity of the overall electrode system.

Carbon innercoated ordered porous TiO2 as anode materials for lithium-ion batteries

“…The diameter of the coated TiO 2 sample is consistent with the data obtained from the SEM image. It should be noted that the carbon layer attached to either side of the pieces, which would be high-speed channels for lithium ion migration [5,14,24]. Unfortunately, porous TiO 2 were not completely covered by a carbon layer.…”

Low-temperature one-step solid-phase synthesis of carbon-encapsulated TiO2 nanocrystals as anode materials for lithium-ion batteries

“…However, both of the lithium-ion diffusivity and electronic conductivity of TiO 2 are relatively low, which can adversely affect the rate capability of LIBs [10]. To address the negative issues, TiO 2 in various nanocrystalline forms are widely used to reduce the diffusion path length for lithium-ions and increase high contact area between electrolyte and electrode, thereby improving both storage capacity and rate capability [11][12][13]. Another common strategy involves incorporation of TiO 2 with carbonaceous materials, which can enhance the electronic conductivity and suppress the aggregation of TiO 2 nanocrystals, thus increasing the anode stability during cycling [14][15][16].…”

Nitrogen-treated Hierarchical Macro-/Mesoporous TiO2 Used as Anode Materials for Lithium Ion Batteries with High Performance at Elevated Temperatures

“…However, low intrinsic electrical conductivity has impeded its application in practice [8,9]. To solve this problem, nanostructuring is often implemented and it has been proved to be effective in improving the electrochemical performance of TiO 2 at room temperature via shortening Li-ion and electron diffusion paths, enlarging the electrode/electrolyte interfacial area, and facilitating strain relaxation during the insertion/extraction processes [10][11][12][13]. However, the complicated fabrication process and relatively low yields are major problems to restrain this method from practical applications.…”